Do you ever feel like people don't get you, you come across in the wrong way, even with your friends?

Because people keep acting really weird with me, my friend used to talk to me everyday but now she ignores me, and she's on Facebook posting on our other friend's wall and urgh. Whenever I'm upset she never wants to hear about it. I just feel really lonely and pointless. I'm shy so I hardly open up to people but the rare times I do they don't even care and they get me so wrong :/